Add Stackset Resource

[xiwhuang]

Description of changes:

Added new resource AWS::CloudFormation::StackSet

Lastest Revision:

• Refactored handler implementations using Call Chaining Pattern.
• Deleted AwsCredentialsExtrator as it is no longer needed.
• Updated to use GetTemplateSummary to validate template.

Testing

Unit Tests

• 97% Instructions Cov.
• 92% Branches Cov.

Manually tests

• StackSet without StackInstances CREATE/DELETE/UPDATE
• StackSet with StackInstances CREATE/DELETE/UPDATE
• StackSet CREATE/DELETE/UPDATE with TemplateURL/TemplateBody
• Negative Tests with Invalid Template
  • Unsupported regions
  • Embedded Stack/StackSet
  • Invalid TemplateURL/ TemplateBody
• Template with Outputs

Known limitation

• TemplateURL and OrganizationUnitIds can be not retrieve in READ/LIST handlers as StackSet API currently does not allow to do so.

Simple Working Template

Resources:
  MyStackSet:
    Type: AWS::CloudFormation::StackSet
    Properties:
      PermissionModel: SELF_MANAGED
      TemplateBody: |
        {
          "AWSTemplateFormatVersion": "2010-09-09",
          "Resources": {
            "IntegrationTestWaitHandle": {
              "Type": "AWS::CloudFormation::WaitConditionHandle",
              "Properties": {}
            }
          }
        }
      StackInstancesGroup: 
        - Regions:
            - us-east-1
            - us-west-2
          DeploymentTargets:
            Accounts:
              - 111111111111
      Tags:
        - Key: key1
          Value: value1
Outputs:
  StackSetId:
    Value: !Ref MyStackSet

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[ammokhov]

use call chaining pattern plz

[ammokhov]

progress chain looks good

[guanghug]

Reviewed the StackSets logics are fine.

[wbingli]

LGTM

[wbingli]

NIce!

Comments have been addressed

[yinglonw]

This should be an array of the capabilities.

[xiwhuang]

Yes, capabilities should be an array. This is the Capability in definitions which will be referenced in Capabilities in properties.

[s0enke]

Great work! Is there a timeframe for bringing this to official CloudFormation (e.g. https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/ReleaseHistory.html)?

[benbridts]

It might also be useful to change the state in the coverage roadmap:
aws-cloudformation/cloudformation-coverage-roadmap#102

Additionally is their work planned for having separate StackInstance resources? I can see value in being able to define the StackSet in one Stack and StackInstances in another (aws-cloudformation/cloudformation-coverage-roadmap#103).